[ThinLTO] Add call edges' relative block frequency to per-module summary.

Summary:
This allows relative block frequency of call edges to be passed to the
thinlink stage where it will be used to compute synthetic entry counts
of functions.

Reviewers: tejohnson, pcc

Subscribers: mehdi_amini, llvm-commits, inglorion

Differential Revision: https://reviews.llvm.org/D42212

llvm-svn: 323349

1 files changed, 35 insertions, 0 deletions

diff --git a/llvm/test/Bitcode/thinlto-function-summary-callgraph-relbf.ll b/llvm/test/Bitcode/thinlto-function-summary-callgraph-relbf.ll
new file mode 100644
index 00000000000..779acada520
--- /dev/null
+++ b/llvm/test/Bitcode/thinlto-function-summary-callgraph-relbf.ll
@@ -0,0 +1,35 @@
+; Test to check the callgraph in summary
+; RUN: opt -write-relbf-to-summary -module-summary %s -o %t.o
+; RUN: llvm-bcanalyzer -dump %t.o | FileCheck %s
+
+
+; CHECK: <SOURCE_FILENAME
+; CHECK-NEXT: <GLOBALVAR
+; CHECK-NEXT: <FUNCTION
+; "func"
+; CHECK-NEXT: <FUNCTION op0=17 op1=4
+; CHECK:       <GLOBALVAL_SUMMARY_BLOCK
+; CHECK-NEXT:    <VERSION
+; See if the call to func is registered.
+; CHECK-NEXT:    <PERMODULE_RELBF {{.*}} op4=1 {{.*}} op7=1
+; CHECK-NEXT:  </GLOBALVAL_SUMMARY_BLOCK>
+; CHECK: <STRTAB_BLOCK
+; CHECK-NEXT: blob data = 'undefinedglobmainfunc{{.*}}'
+
+
+; ModuleID = 'thinlto-function-summary-callgraph.ll'
+target datalayout = "e-m:e-i64:64-f80:128-n8:16:32:64-S128"
+target triple = "x86_64-unknown-linux-gnu"
+
+; Function Attrs: nounwind uwtable
+define i32 @main() #0 {
+entry:
+    call void (...) @func()
+    %u = load i32, i32* @undefinedglob
+    ret i32 %u
+}
+
+declare void @func(...) #1
+@undefinedglob = external global i32
+
+; OLD: Index {{.*}} contains 1 nodes (1 functions, 0 alias, 0 globals) and 1 edges (0 refs and 1 calls)